The smoke (ho kapnos). Old word, in N.T. only Act 2:19; Rev 8:4; Rev 9:2., Rev 9:17.; Rev 14:11; Rev 15:8; Rev 18:9, Rev 18:18; Rev 19:3. Here from the incense in the angel’s hand.
With the prayers (tais proseuchais). So associative-instrumental case, but it may be dative as in Rev 8:3 (for).